Question
I have an area 20 feet long and 3 feet wide bordering a cement driveway on one side and the house on the other.  This is a newly developed area with new, very fertile soil obtained from a cattle feedlot.  The problem is, the bed is only about 4 inches deep before you hit an old concrete slab.  What would you suggest to plant in this area that doesn't require a deep root system?  I would like a hedge of some sort, flowering would be even better.  I live in Zone 6.  Thank-you

Answer
Hi Susan, You have a very difficult situation.  The soil isn't deep enough to support shrubs. Winter kill is likely, summer watering will be a nightmare and any tall plants will probably topple over.  Even most perennials and annuals will struggle as they mature with that little soil.  I have another concern about whether this area holds water since there is a slab under it.
I would suggest a retainer wall of rock or brick along the driveway at least 12" high to get you 16" or more of soil depth.
If that's not possible, then I'd plant drought tolerant groundcovers.  Which one would depend on how much sun this area gets but sedum would be nice. Jim